science

When you’re doing two things at once – like listening to the radio while driving – your brain organizes itself into two, functionally independent networks, almost as if you temporarily have two brains. That’s according to a fascinating new study from University of Wisconsin-Madison neuroscientists Shuntaro Sasai and colleagues.

Remembering the past is a complex phenomenon that is subject to error. The malleable nature of human memory has led some researchers to argue that our memory systems are not oriented towards flawlessly preserving our past experiences. Indeed, many researchers now agree that remembering is, to some degree, reconstructive. Current theories propose that our capacity to flexibly recombine remembered information from multiple sources – such as distributed memory records, inferences, and expectations – helps us to solve current problems and anticipate future events. One implication of having a reconstructive and flexible memory system is that people can develop rich and coherent autobiographical memories of entire events that never happened.

In this article, we revisit questions about the conditions under which participants in studies of false autobiographical memory come to believe in and remember fictitious childhood experiences. […]

Approximately one-third of participants showed evidence of a false memory, and more than half showed evidence of believing that the [fictitious] event occurred in the past.

Most people strongly believe they are just, virtuous, and moral; yet regard the average person as distinctly less so. This invites accusations of irrationality in moral judgment and perception — but direct evidence of irrationality is absent. Here, we quantify this irrationality and compare it against the irrationality in other domains of positive self-evaluation. […]

Virtually all individuals irrationally inflated their moral qualities […] Irrational moral superiority was not associated with self-esteem. Taken together, these findings suggest that moral superiority is a uniquely strong and prevalent form of “positive illusion,” but the underlying function remains unknown.

The idea behind power poses, that if you stand in a “powerful” position, broad posture, hands on hips, shoulders high and pushed back, you will suddenly feel psychologically and physiologically stronger, is intuitively appealing, especially for people without much confidence. The problem is that it’s simply not true, according to University of Pennsylvania researchers. […]

“We did find that […] if you’re a loser and you take a winner or high power pose, your testosterone decreases.”

In other words, Smith said, “people might not be able to ‘fake it until they make it,’ and in fact it might be detrimental.”

The Dress photograph, first displayed on the internet in 2015, revealed stunning individual differences in color perception. The aim of this study was to investigate if lay-persons believed that the question about The Dress colors was answerable. Past research has found that optimism is related to judgments of how answerable knowledge questions with controversial answers are. Furthermore, familiarity with a question can create a feeling of knowing the answer.

Building on these findings, 186 participants saw the photo of The Dress and were asked about the correct answer to the question about The Dress’ colors (“blue and black,” “white and gold,” “other, namely…,” or “there is no correct answer”). Choice of the alternative “there is no correct answer” was interpreted as believing the question was not answerable. This answer was chosen more often by optimists and by people who reported they had not seen The Dress before.

When one draws a correlation between body mass and brain mass for living primates and extinct species of Homo, it is not humans—whose brains are three times larger than those of chimpanzees, their closest primate relative—that are an outlier. Instead, it is the great apes—gorillas and the orangutan—with brains far smaller than would be expected in relation to their body mass. We are the new normal in evolution while the great apes are the evolutionary oddity that requires explanation.

But we remain special in another way. Our 86 billion neurons need so much energy that if we shared a way of life with other primates we couldn’t possibly survive: there would be insufficient hours in the day to feed our hungry brain. It needs 500 calories a day to function, which is 25 percent of what our entire body requires.

Size has been one of the most popular themes in monster movies, especially those from the 1950s. The premise is invariably to take something out of its usual context–make people small or something else (gorillas, grasshoppers, amoebae, etc.) large–and then play with the consequences. However, Hollywood’s approach to the concept has been, from a biologist’s perspective, hopelessly naïve. Absolute size cannot be treated in isolation; size per se affects almost every aspect of an organism’s biology. Indeed, the effects of size on biology are sufficiently pervasive and the study of these effects sufficiently rich in biological insight that the field has earned a name of its own: “scaling.” […]

Take any object–a sphere, a cube, a humanoid shape. […] If you change the size of this object but keep its shape (i.e., relative linear proportions) constant, something curious happens. Let’s say that you increase the length by a factor of two. Areas are proportional to length squared, but the new length is twice the old, so the new area is proportional to the square of twice the old length: i.e., the new area is not twice the old area, but four times the old area (2L x 2L).

Similarly, volumes are proportional to length cubed, so the new volume is not twice the old, but two cubed or eight times the old volume (2L x 2L x 2L). As “size” changes, volumes change faster than areas, and areas change faster than linear dimensions.

[…]

In The Incredible Shrinking Man (1957), the hero is exposed to radioactive toxic waste and finds himself growing smaller and smaller. When he stops shrinking, he is about an inch tall, down by a factor of about 70 in linear dimensions. Thus, the surface area of his body, through which he loses heat, has decreased by a factor of 70 x 70 or about 5,000 times, but the mass of his body, which generates the heat, has decreased by 70 x 70 x 70 or 350,000 times. He’s clearly going to have a hard time maintaining his body temperature (even though his clothes are now conveniently shrinking with him) unless his metabolic rate increases drastically.

Luckily, his lung area has only decreased by 5,000-fold, so he can get the relatively larger supply of oxygen he needs, but he’s going to have to supply his body with much more fuel; like a shrew, he’ll probably have to eat his own weight daily just to stay alive. He’ll also have to give up sleeping and eat 24 hours a day or risk starving before he wakes up in the morning (unless he can learn the trick used by hummingbirds of lowering their body temperatures while they sleep).

Because of these relatively larger surface areas, he’ll be losing water at a proportionally larger rate, so he’ll have to drink a lot, too.

After four minutes of interaction with partners with high levels of depressive symptoms, participants did not experience increased negative affect; instead, they experienced reduced positive affect, which led to the rejection of these partners.

Many laboratory experiments show that people are often altruistic or care for fairness. We present data that reveal a darker side of human nature. We introduce the joy-of-destruction game. Two players each receive an endowment and simultaneously decide on how much of the other player’s endowment to destroy. Subjects play this game repeatedly. In one treatment, subjects can hide their destruction behind random destruction. In this treatment, money is destroyed in almost 40% of all decisions. We attribute this behavior to a visceral pleasure of being nasty. Under full information destruction is also observed, but rare. In this treatment, acts of destruction are followed by immediate retaliation.